Cloud ComputingTraditional Sever ConceptOutlinePros and ConsVirtual Server ConceptHypervisors and hostsVirtual machinesPros and ConsCould ComputingConceptThe Rise of CloudExamplesData centresOverview

Ideas/Slides from Norman Wilde & Thomas Huber, UWF and Mark Baker

Two Technologies for AgilityVirtualization:The ability to run multiple operating systems on a single physical system and share the underlying hardware resources*Cloud Computing:The provisioning of services in a timely (near on instant), on-demand manner, to allow the scaling up and down of resources**

* VMware white paper, Virtualization Overview** Alan Williamson, quoted in Cloud BootCamp March 2009

The Traditional Server ConceptWeb ServerWindowsIISApp ServerLinuxGlassfishDB ServerLinuxMySQLEMailWindowsExchange

The Traditional Server ConceptSystem Administrators often talk about servers as a whole unit that includes the hardware, the OS, the storage, and the applications.Servers are often referred to by their function i.e. the Exchange server, the SQL server, the File server, etc.If the File server fills up, or the Exchange server becomes overtaxed, then the System Administrators must add in a new server.

And if something goes wrong ...Web ServerWindowsIISApp ServerDOWN!DB ServerLinuxMySQLEMailWindowsExchange

The Traditional Server ConceptUnless there are multiple servers, if a service experiences a hardware failure, then the service is down.System Admins can implement clusters of servers to make them more fault tolerant. However, even clusters have limits on their scalability, and not all applications work in a clustered environment.

The Traditional Server ConceptProsEasy to conceptualizeFairly easy to deployEasy to backupVirtually any application/service can be run from this type of setupConsExpensive to acquire and maintain hardwareNot very scalableDifficult to replicateRedundancy is difficult to implementVulnerable to hardware outagesIn many cases, processor is under-utilized

The Virtual Server ConceptVirtual servers seek to encapsulate the server software away from the hardwareThis includes the OS, the applications, and the storage for that server.Servers end up as mere files stored on a physical box, or in enterprise storage.One host typically house many virtual servers (virtual machines or VMs).A virtual server can be serviced by one or more hosts e.g. storage, services, etc

The Virtual Server ConceptHypervisor layer between Guest OS and hardware

Hypervisors And HostsA hypervisor is a piece of computer software, firmware or hardware that creates and runs virtual machines.A computer on which a hypervisor is running one or more virtual machines is defined as a host machine. Each virtual machine has a guest operating systems, which is managed by the hypervisor. Multiple instances of a variety of operating systems may share the virtualized hardware resources.

Hypervisors and Virtual Machinesx86 ArchitectureHypervisorServer1Guest OSServer2Guest OSClustering

Service ConsoleIntercepts hardware requests

The Virtual Server ConceptVirtual servers can still be referred to by their function i.e. email server, database server, etc.If the environment is built correctly, virtual servers will not be affected by the loss of a host.Hosts may be removed and introduced almost at will to accommodate maintenance.

The Virtual Server ConceptVirtual servers can be scaled out easily.If the administrators find that the resources supporting a virtual server are being taxed too much, they can adjust the amount of resources allocated to that virtual serverServer templates can be created in a virtual environment to be used to create multiple, identical virtual serversVirtual servers themselves can be migrated from host to host almost at will.

The Virtual Server ConceptProsResource poolingHighly redundantHighly availableRapidly deploy new serversEasy to deployReconfigurable while services are runningOptimizes physical resources by doing more with lessConsSlightly harder to conceptualizeSlightly more costly (must buy hardware, OS, Apps, and now the abstraction layer)

Cloud ComputingSource: http://www.free-pictures-photos.com/

Cloud Computing?The cloud is Internet-based computing, whereby shared resources, software, and information are provided to computers and other devices on demand pay per use.Cost-effective means of virtualising and making use of resources more effectivelyLow start-up costs pay for use helps to kick-start companiesScaling is proportional to demand (revenue) so its a good business modelVast range of Cloud Computing applicationsVirtual private servers, Web hosting, data servers, fail-over services, etc

Clouds are on the Rise

Basic Cloud CharacteristicsThe no-need-to-know in terms of the underlying details of infrastructure, applications interface with the infrastructure via the APIs.The flexibility and elasticity allows these systems to scale up and down at willutilising the resources of all kindsCPU, storage, server capacity, load balancing, and databasesThe pay as much as used and needed type of utility computing and the always on, anywhere and any place type of network-based computing.*

Basic Cloud CharacteristicsCloud are transparent to users and applications, they can be built in multiple ways branded products, proprietary open source, hardware or software, or just off-the-shelf PCs.In general, they are built on clusters of PC servers and off-the-shelf components plus Open Source software combined with in-house applications and/or system software.*

Motivation Example: Forbes.comYou offer on-line real time stock market dataWhy pay for capacity weekends, overnight?

9 AM - 5 PM,M-FALL OTHER TIMESRate of Server Accesses

Forbes' SolutionHost the web site in Amazon's EC2 Elastic Compute CloudProvision new servers every day, and deprovision them every nightPay just $0.10* per server per hour* more for higher capacity serversLet Amazon worry about the hardware!

Cloud computing takes virtualization to the next stepYou dont have to own the hardwareYou rent it as needed from a cloudThere are public cloudse.g. Amazon EC2, and now many others (Microsoft, IBM, Sun, and others ...)A company can create a private oneWith more control over security, etc.

Goal 1 Cost ControlCostMany systems have variable demandsBatch processing (e.g. New York Times)Web sites with peaks (e.g. Forbes)Startups with unknown demand (e.g. the Cash for Clunkers program)Reduce riskDon't need to buy hardware until you need it

Goal 2 - Business AgilityMore than scalability - elasticityEly Lilly in rapidly changing health care businessUsed to take 3 - 4 months to give a department a server cluster, then they would hoard itUsing EC2, about 5 minutesAnd they give it back when they are doneScaling back is as important as scaling up

Goal 3 - Stick to Our BusinessMost companies don't WANT to do system administrationForbes says:We are is a publishing company, not a software companyBut beware:Do you really save much on sys admin?You don't have the hardware, but you still need to manage the OS!

Cloud Computing Overview

SaaS and PaaSSaaS is where an application is hosted as a service provided to customers across the Internet. Saas alleviates the burden of software maintenance/supportbut users relinquish control over software versions and requirements.PaaS provides a computing platform and a solution stack as a service. Consumer creates the software using tools and/or libraries from the provider. The consumer also controls software deployment and configuration settings. The provider provides the networks, servers, storage and other services.*

IaaSIaaS providers offer virtual machines, virtual-machine image libraris, raw (block) and file-based storage, firewalls, load balancers, IP addresses, virtual local area networks (VLANs), and software bundles.Pools of hypervisors can scale services up and down according to customers' varying requirements All infrastructure is provided on-demand

Cloud Service Models*Software as a Service (SaaS)Platform as a Service (PaaS)Infrastructure as a Service (IaaS)SalesForce CRMLotusLiveAdopted from: Effectively and Securely Using the Cloud Computing Paradigm by peter Mell, Tim Grance

Some Commercial Cloud Offerings*

Cloud Taxonomy*

Where is all of this?

Data Centers10 billion spent on electricity per year for data centers3% of global energy useClouds are the future of the way companies do business on the Internet

Data Centers By Size and Region

Summary CommentsVirtualization of servers solves a lot of headaches when deploying infrastructure and applicationsIt allows servers to be backed up and moved around seamlesslyMigrating a server might allow an application speed to increase e.g. move to a faster machine Resizing (up or down) keeps costs proportional to business modelThe model works for both private clouds or public ones (insourcing or outsourcing)The cloud is easy to understand and a convenient way of accessing infrastructure and services.

*IaaSdelivers computer infrastructure, typically a platform virtualization environment, as a service. Rather than purchasing servers, software, data center space or network equipment, clients instead buy those resources as a fully outsourced service. PaaSdeliver a computing platform where the developers can develop their own applications.SaaSis a model of software deployment where the software applications are provided to the customers as a service.

*http://www.opencrowd.com/assets/images/views/views_cloud-tax-lrg.png*